


406 Not Acceptable

by antivanitas



Series: A Creampie is Not a Pastry [2]
Category: Big Hero 6 (2014)
Genre: Heavy Petting, M/M, Possessive Behavior, Sibling Incest, Teasing, Yandere Tadashi
Language: English
Status: Completed
Published: 2015-03-12
Updated: 2015-03-12
Packaged: 2018-03-17 11:45:21
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,734
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3528197
Author URL: https://archiveofourown.org/users/antivanitas/pseuds/antivanitas
Summary: <blockquote class="userstuff">
              <p>“Did you fuck someone else?”  His thighs tighten around Hiro’s waist.  Trapped.  “Did they make you cum?”</p><p>Hiro is shaking.  His spine curves and he tries to turn his head so he can capture Tadashi’s lips, but to no avail.  “T-Tadashi…”</p><p>“Answer me.”</p><p>His voice is dark and low.  Hiro swallows noisily and shakes his head gently, but Tadashi isn’t satisfied.  Someone left that mark there—he has to make sure no one does that ever again unless it’s him.</p>
            </blockquote>





	406 Not Acceptable

**Author's Note:**

> its back

For a while, Tadashi tries to ignore what happened.

After dinner, he’s silent.  Hiro tries to practically throw himself at his older brother, probably thinking it’s merely the next step in their “relationship” (whatever fucked up conditions even constitute that word is beyond Tadashi), but he’s sorely disappointed when Tadashi gently pushes him away.  When Tadashi curls up in bed and turns out the light and barely mumbles that Hiro should do the same.  His heart practically collapses in on itself when he hears sniffles and erratic breathing from the other side of the room.

But they _can’t_.  They can’t make out like lovers.  They certainly can’t have sex.  What would Aunt Cass say if she ever found out?  The gang?  The _cops_?  He’s pretty sure he’s going to Hell already for just those few seconds of bliss—

No.  Not bliss.  Tadashi rolls over and blinks at the ceiling.  His brother wants to fuck him and he keeps saying no to protect him; that’s all that’s happening here.

 _You wanted it_ , a voice in his head tells him.  _You loved it_.

Hiro sniffles again.

The next morning, Tadashi opens his eyes to the bright sunlight streaming in through the window, a haze of steam rolling in from the bathroom, and his baby brother standing stark naked in full view at the mirror.

His first reaction is to stare.  And it _shouldn’t_ be.  His eyes roam Hiro’s slightly muscular back, the scratches he left yesterday, how his hips jut out the perfect amount, the water running down his flawless skin to his tight ass.   Tadashi bites his lip.  In a sleep-induced haze he wonders what it would be like to fuck Hiro in the shower, holding his pretty little waist and keeping him facing the wall while Tadashi pounds into him from behind.  How it would feel for Hiro to give him a soapy handjob, all while pleading for his brother to fill him up.

Hiro needs something from the cabinet, and he bends down abruptly to get to it.  Tadashi can see a full view of exactly where he wants to be buried before he finally snaps out of it and covers his eyes with the blanket.

“Put some damn pants on,” he grumbles from under the fabric.  He hears Hiro scoff, shuffle over and stop just before Tadashi’s bed.

“Not anything you haven’t seen before,” Hiro says gruffly.  His voice sounds hoarse, probably from crying, and Tadashi’s stomach fills with acid.  “Look at these scratches you left me!”

Tadashi had looked.  It had burned into his retinas and it made his cock twitch.

Hiro clicks his tongue and walks away and Tadashi doesn’t look until he hears the rustle of his brother putting on a pair of pants.  He sits up in bed and very pointedly does not look at Hiro while he gets up and wanders to his dresser.

Tadashi pauses.  He takes one look at Hiro, glances at the bathroom, and wastes no time making a direct line for it.

“Oh, come _on_.”  Hiro steps in front of Tadashi, arms wide.  “You’re avoiding me now?  How many times have you changed in front of me?  A million, that’s how many.”

God damnit.  He’s going to fight for this, isn’t he?  What Hiro wants, Hiro gets.  Tadashi closes his eyes and runs a hand through his hair, exhaling slowly, trying to remember how to think when he’s faced with his shirtless brother.  When did that start happening, anyway?

“Hiro,” he begins sternly, “You’re my brother.  And I love you.  But we can’t do this.”

Hiro’s eyes well up with tears, but he manages to be a smart ass anyway.  “You _liked_ it, asshole!  You called me a nau--”

“Just stop, okay?  Jesus.”  Tadashi spins in place and slams the bathroom door.  Once he’s safely in solitude, he sinks to the floor with his back to the wall and rubs both hands over his face, like he’s trying to scrub off his sins.  Hiro can’t be convinced like this and Tadashi is convinced the only way to stop this weird, incestual phase of his is to leave him be.

So he starts sleeping in the spare room.  Aunt Cass is suspicious, but Tadashi just says his mattress is crap and needs replacing soon.  He stops driving Hiro to school because when he does, his younger brother whimpers in his ear and drags his fingers up Tadashi’s shirt.  He stops working on his projects in the garage and chooses to just stay at school longer hours.

Hiro is growing absolutely restless.  Walking out naked in front of Tadashi didn’t work at all, _somehow_ , and all of his attempts to get his brother in bed have been for null.  He’s honestly running out of ideas.  Popsicles haven’t worked, even when the melting treat drips down his chin and Tadashi can clearly see Hiro’s pink tongue swipe at the liquid before he moans about how good it is. 

He has a last resort, but it’s playing dirty.  Hiro supposes there’s no other option.

Tadashi comes home one day, exhausted from working on his robotics project until ten, and expects Hiro to already be sleeping.  Even if he’s cautious about his younger brother these days, he still _loves_ him.  Tadashi pokes his head in their room for a moment, ready to brush his teeth and climb into the guest bed, but what he sees makes his whole world stop turning.

Hiro is in his normal position, seated at his computer without a shirt on and wearing a pair of boxers.  This is a usual sight.  What _isn’t_ usual is the dark, _dark_ purple and red bruise on the side of Hiro’s neck.

“ _What_ the fuck is that?”

Hiro turns to him innocently, realizes what Tadashi is looking at, and slaps a hand to his neck to cover the mark.  “T-Tadashi!  I thought you said you’d be at Fred’s tonight—“

Tadashi can’t see anything besides Hiro and red.  Someone touched him.  Someone put their mouth on his little brother.  Images flash through Tadashi’s mind, of Hiro pressed to a wall with a shadow of a person making him gasp and writhe and moan.  Of Hiro shivering and on the verge of coming.  He doesn’t even realize stepping forward and yanking Hiro out of the computer chair.

“Tadashi, _wait_ , I can explain.”

He doubts it.  Tadashi’s face is entirely blank.  He doesn’t speak as he pushes Hiro to his own bed and shoves him on it.

There’s a kind of methodical concentration to his actions when Tadashi stalks over Hiro like he’s capturing his prey.  His eyebrows knit together, jaw set tight, straddling his little brother and standing on his knees to rip his shirt off.

Hiro’s pupils dilate immediately.  Tadashi watches as Hiro’s eyes roam slight muscles and a toned stomach with a heated gaze.  Did he do that for someone else?  Is Hiro so desperate to get fucked that he went to someone else, bent over for them and offered himself?  Tadashi’s breathing picks up dramatically when his mind’s eye shows him Hiro with his ass in the air, legs spread and cum dripping down his thighs.

Tadashi is pulled violently out of his thoughts when Hiro’s tiny hands glide up his stomach.  His lithe fingers dip into every crevice, moving ever upwards until they reach his nipples.  Hiro rubs gently with his thumb, and Tadashi gasps, arching his back into the feeling.  Fuck, who knew those were that sensitive?

Hiro shifts below him and his arousal becomes obvious.  That was _quick_.  Tadashi scowls, grabs Hiro’s wrists and pins them beside his head.  He leans in close to his little brother’s ear and whispers fiercely.

“Did you fuck someone else?”  His thighs tighten around Hiro’s waist.  Trapped.  “Did they make you cum?”

Hiro is shaking.  His spine curves and he tries to turn his head so he can capture Tadashi’s lips, but to no avail.  “T-Tadashi…”

“ _Answer me._ ”

His voice is dark and low.  Hiro swallows noisily and shakes his head gently, but Tadashi isn’t satisfied.  Someone left that mark there—he has to make sure no one does that ever again unless it’s _him_.

Tadashi’s lips graze the bruise and he bites down a moment later.  Hiro cries out, but his voice is laced with a kind of pleasure that Tadashi realizes Aunt Cass will recognize if she hears him.  Quickly, he covers Hiro’s mouth with his hand and makes marks all down his neck, until he’s kissing down Hiro’s chest.

“ _Fuck_ ,” Hiro breathes.  His cock is straining against his boxers and Tadashi smirks.  He bets no one else could make Hiro feel like this; just him.  Just his older brother.  “Tadashi--”

Tadashi drags a finger down Hiro’s clothed arousal.  “No.  What do you call me when you want something, Hiro?  Be polite.  You let someone else touch you and I deserve respect.”

Hiro is quaking.  His hands stay obediently above his head, gripping onto the headboard for purchase.  “Nii-san…I’m sorry…”

“ _No_.”

“A-Aniki!  Aniki, _please_.”

That’s better.  Tadashi smirks and grips Hiro through his boxers.  Hiro is warm and solid and _rock hard_ in his palm.  He loves the way it looks when he starts massaging his little brother’s cock until a wet spot forms in the boxers.

And then, he sees a smear on Hiro’s neck.

Tadashi pauses.  The heat leaves his body.  He reaches up while Hiro is still trying to find his breath, brushes his finger across the bruise, and blue powder comes off on his finger.

“You little _shit_.”

Hiro’s eyes go wide, and he immediately tries to sit up and keep his brother in place by wrapping his arms frantically around his neck.  “Wait!  I just—I wanted you so _bad_ and you kept rejecting me!”

Tadashi doesn’t even hear him.  His stomach boils with anger and arousal and _he just nearly fucked his brother_ for the _second time_.  A switch flips in his mind.  Should he even try to hide it anymore?  Should he go through torture every day of his life while Hiro teases him until he gives in?

He grips Hiro’s chin with his fingers and kisses him hard.  Hiro’s body goes still, a tiny whimper resonating in his chest, and he nearly melts into it.  But before he can, Tadashi pulls away and bumps their foreheads together.

“We’re gonna need rules,” he says gruffly.

Hiro grins.

**Author's Note:**

> on tumblr @ genderfluidstanmarsh c:


End file.
